Driver cause Copy-on-Write RRS feed

  • Question

  • Is it possible to have driver code when writing to a user mode VA cause a COW to occur? I have read conflicting answers to this and would like a definitive answer.
    Tuesday, September 30, 2014 5:11 PM


  • Certainly it is possible.  Declare a static or global buffer, and ask the driver to fill it, the system will do a copy on write of the pages with the buffer. 

    A more interesting question is why should you care?  This is handled by the cache manager, and should not impact any reasonably written driver.

    Don Burn Windows Filesystem and Driver Consulting Website:

    Tuesday, September 30, 2014 5:42 PM